Linux v5.2-rc1 - nilfs2
tristate "NILFS2 file system support"
NILFS2 is a log-structured file system (LFS) supporting continuous
snapshotting. In addition to versioning capability of the entire
file system, users can even restore files mistakenly overwritten or
destroyed just a few seconds ago. Since this file system can keep
consistency like conventional LFS, it achieves quick recovery after
NILFS2 creates a number of checkpoints every few seconds or per
synchronous write basis (unless there is no change). Users can
select significant versions among continuously created checkpoints,
and can change them into snapshots which will be preserved for long
periods until they are changed back to checkpoints. Each
snapshot is mountable as a read-only file system concurrently with
its writable mount, and this feature is convenient for online backup.
Some features including atime, extended attributes, and POSIX ACLs,
are not supported yet.
To compile this file system support as a module, choose M here: the
module will be called nilfs2. If unsure, say N.